Are there nice sequencers/daws with very good notation/score editor (along with VSTi/plugin support for rendering the score).

I know Cubase etc offer usable score editors. I'd prefer to work with the entire musical work as the score (as in Sibelius etc). I've used Harmony Assistant for sometime. Liked it very much. It has an internal sound synth, doesn't support vst plugins.

I believe Sibelius and Pro Tools are integrated, so you can write in Sibelius and import cleanly into Pro Tools, where you can use Pro Tools TDM or RTAS plugins. I have never done this personally though, so consider this hearsay :)

"Decent" makes this a bit subjective (and heck, tool questions can border on religious from time to time) but I'll recommend looking at Logic Pro.

I moved from a Cubase SX 3 to Logic 8 Pro system three years ago. I used to think SX 3's scoring capabilities were decent to pretty good but Logic, once I got used to the Mac and the Logic way of working, does a fantastic job at managing score writing and playback. You can move between piano roll and score editing. Because it's completely integrated with Logic you can audition the scores with whatever VSTi's you'd like to use (and Logic Pro comes with some impressive and extensive VSTi's). And you can produce some very nice looking printed score sheets at the end. I've scored about a dozen pit band pieces with Logic 8 now and I'm a convert.

This tutorial covers producing printed sheet music, but it gives you a good overview and you can see the screens you'd be working with.

+1 I have used Cakewalk (in the "old days"), Cubase and Pro Tools and Logic's piano roll and score editors are both really nice tools within a great overall package. But like Ian says, the Logic way of working takes some getting used to.
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bogeyminDec 10 '10 at 23:55